Studies On Isolation, Screening And Identification Of Symbiotic Or Epiphytic Actinomycetes And Fungi From Marine Fish

In this study, we isolated marine actinomycetes and fungi from migratory marine fish which were collected from Pingtan sea side in Fujiang province. We total isolated 45 marine actinomycetes and 186 marine fungi by combining kinds of medium and antibiotics in five times.We screend actinomycete strain 080101 which was highly efficient against Pyricularia grisea and broad-spectrum activity against pathogenic fungi strains by screening against Pyricularia grisea.We found that 2 marine actinomycetes strains and 9 marine fungi strains against TMV replication, and about 10% strains exceed 50% against TMV infection by screening anti-TMV in all actinomycetes and fungi strains.Anti-tumor activity of fermentation products from marine fungi was determined by MTT methods, the result indicated that strain 040103 highly inhibited HHCC BEL-7404 and HGCC SGC-7901.By studying colonial morphology, cultural characteristics, physiological and biochemical characteristics, and 16S rRNA, strain 080101 was preliminary proposed Streptomyces globisporus and strain 040103 was preliminary proposed Streptomyces hygroscopicus.We modified the fermentation conditions on the production of strain 080101 fermentation broth against Pyricularia grisea. The optimum culture includes:soluble starch 1.5%, glycerol 0.5%, soybean flour 1%, corn starch 1%. The condition of culture includes:artificial sea water 50%, initial pH 6, seed cultural time 2-3d, inoculation amount 6%, fermentation time 2-3 d, medium volume 200 mLin conical flask of 500mL. Under the optimized conditions, the fermentation broth inhibitory rates against Pyricularia grisea was about 10% higher than before.